The try...except statement now has an optional else
clause, which must follow all except clauses. It is useful to
place code that must be executed if the try clause does not
raise an exception. For example:
for arg in sys.argv:
try:
f = open(arg, 'r')
except IOError:
print 'cannot open', arg
else:
print arg, 'has', len(f.readlines()), 'lines'
f.close()